Russia’s Security Council has accused the United States of plotting to oust President Vladimir Putin by aiding opposition groups.

Nikolai Patrushev, the council’s chief, said on Wednesday that Washington is financing the opposition and encouraging mass demonstrations against Putin.

Patrushev added that the US funds Russian political groups under the guise of promoting civil society, just as in the “color revolutions” in the former Soviet Union republics.

He went on to say that Washington also uses sanctions over the Ukraine crisis as a “pretext” to inflict economic pain and cause discontent.

Combating color revolutions

“It’s clear that the White House has been counting on a sharp deterioration in Russians’ standard of living, mass protests,” Patrushev said, adding that Moscow can stand against the pressure thanks to its resilience and “decades of experience in combating color revolutions.”

The comments come a week after a Russian protest leader was murdered near the Kremlin. Russia’s Putin described as politically motivated the killing of Boris Nemtsov, a former deputy premier, who had joined the opposition.

Russian President Vladimir Putin has called for an end to “shameful” political murders in his country, following the killing of the Kremlin critic.

US officials have dismissed the suggestion of a plot, with White House spokesman Josh Earnest calling the idea “outrageous and false.”

US President Barack Obama also has prolonged the anti-Russia sanctions introduced on March 6, 2014 “to deal with the unusual and extraordinary threat to the national security and foreign policy of the United States.”

The sanctions were imposed by the US and the European Union after they accused Russia of being involved in the Ukrainian conflict that broke out last year. Russia has repeatedly denied the accusation.

The two mainly Russian-speaking regions of Donetsk and Luhansk in the eastern Ukraine have been hit by deadly clashes between pro-Russia forces and the Ukrainian army since Kiev launched military operations in April last year to crush pro-Russia protests there.